Described herein are compositions comprising decellularized cardiac extracellular matrix and therapeutic uses thereof. Methods for treating, repairing or regenerating defective, diseased, damaged or ischemic cells, tissues or organs in a subject, preferably a human, using a decellularized cardiac extracellular matrix of the invention are provided. Methods of preparing cardiomyocyte culture surfaces and culturing cells with absorbed decellularized cardiac extracellular matrix are provided.